Electrical system of distribution.



G. H. FESSENDEN, .IR. ELECTRICAL SYSTEM OF DISTRIBUTION. APPLICATION mco JUNE 6, 1912.

2 SHEETS-SHEET I- Patented Dec. 21, 1915.

G. R. FESSENDEN. IR.

ELECTRICAL SYSTEM OF DISTRIBUTION.

APPLICATION FILED IUNE 6,1912. 1,164,635. Patented Dec.21,1915.

2 SHEETS-SHEET 2.

WW4 70 7 E 77 "fl WITNESSES 76 g; fymvmzfjt @mv L; T L 6L ,4 TTORNEYS UNITED STATES PATENT OFFICE.

GEORGE R. FESSENDEN, JR., OF LANCASTER, NEW YORK, ASSIGNOR T0 GOULD COUPLER COMPANY, A CORPORATION OF NEW YORK.

ELECTRICAL SYSTEM OF DISTRIBUTION.

Application filed June 6, 1912.

To all whom it may concern.

Be it known that I, Gnoaon R. Fnssnxnnx, Jr., a citizen of the United States, and a resident of Lancaster, Erie county, State of New York, have invented certain new and useful Improvements in Electrical Systems of Distribution, of which the following is a specification.

My invention relates to electrical systems of distribution and more especially to systems designed for the lighting, &c., of automobiles, cars and the like.

One object of my invention is to provide an arrangement which is simple and efficient in construction and ope 'ation and which has few moving parts, and which parts are not likely to get out of order.

Further objects, features and advantages will more clearly appear from the detailed description given below taken in connection with the accompanying drawings which form a part of this specification.

Referring to the drawings, Figure 1 is a diagram illustrating a system embodying my invention in one form. Fig. 2 is a similar diagram illustrating a modification. Figs. 3 to 8 illustrate other modifications.

Referring to Fig. 1, 1 represents a main generator connected to the mains 2, 3, for supplying a lamp or work circuit 4 connected across the generator, and in parallel. with the work circuit 4: is a storage battery 5. 6 represents a main shunt field on the generator and connected across the battery 5 at the points 7 and 8. 9 is a switch in the lamp circuit and 10 a switch in circuit with the field G. 11 represents a main switch controlled by a shunt coil 12 connected across the mains 2, 3, and by a series coil 13 in series with the main 3. The switch 11 is adapted to make electrical connection between the contacts 14 and 15 and at the same time connect the coil 18 in series with the main 3. Arranged in series with the main 2 is a fixed resistance 16 of about 0.5 ohm. Connected in shunt between the main 2 at the point 17 and the contact 15, are two fixed resistances 18 and 19, the resistance 18 being about 4 ohms, and the resistance 19 being about 8 ohms. The battery 5 has an effective resistance of approximately 1 ohm. 20 represents a differential or regulating field on the generator 1, one terminal of which field is connected at the point 8 be- Specification of Letters Patent.

Patented Dec. 21, 1913.

Serial No. 702,040.

tween the resistance 10 and battery 5, and the other terminal of which field is connected at the point 21 between the resistances 18 and 19. It will be noticed that when the main switch 11 is closed the resistance 19 and positive end of the battery 5 are practically connected together, the only intervening resistance being the negligible resistance of the coil 13. Under such conditions with the main switch closed it will be seen that the resistances 16, 18 and 19, and the battery 5 form alvheatstone bridge connected across the mains 2, 3, with the battery 5 forming one element or leg thereof, and the work circuit 4 being connected across the battery.

The operation of the arrangement will be clear from the following: Assuming that the generator 1 be driven at a variable speed, as

is customary, and supposing the speed thereof be gradually increased then when the voltage across the mains has risen to the desired value the strength of the coil 19 will become suflicient to close the main switch in a well known manner, whereupon the gen orator supplies current both to the work circuit and battery. If the battery be in a more or less discharged condition, the battery will continue to take more current as the speed increases until the I R drop across the resistance 16 becomes such that there is no difference of potential between the points 8 and 21. Up to this time the current in coil 20 has been in a direction to aid coil 6 and help build up the machine, but upon further increases in speed and resultant increase in I R drop across the resistance 16, a potential drop is created between the points 8 and 21 in the opposite direction, whereby the coil 20 opposes the coil 6 which weakens the field strength of the generator and thus prevents its voltage from increasing materially. As the battery voltage rises due to the battery becoming charged the bridge is affected to similarly regulate the voltage of the generator for this condition. It will thus be seenthat the regulation is dependent on the current in resistance 16 whereby the voltagethereacross is varied and these changes are caused to affect the generator voltage by means of the ll'heatstonc bridge elements, thus avoiding all rheostats and other apparatus having moving parts. The arrows 2 indicate the direction of the battery current when the generator is shut down or the main switch is open.

As shown in Fig. 1, the main switch dis- 5 connects the battery and work circuit from the generator in order. to render the regu-' The modification shown in Fig. 2 embodies substantially the same principles. As there shown the generator 25 supplies the mains 26 and 27 which have connected thereacross the Wheatston e bridge, having as one element a battery 28. The other elements of the Wheatstone bridge comprise the resistance 29 in series with the main 26 and a main field coil 30 on the generator which also acts as a resistance, forming one element of the Wheatstone bridge. In other words, the field not only acts as a main field in the generator 1 but-also performs the functions of the resistance 18 of the system 30 shown in Fig. 1. The other element of the Wheatstone bridge is shown at 32, which corresponds to the resistance 19 of Fig. 1. A main switch is shown at 32 provided with a main shunt controlling coil 33 and 35 a series coil 34, the switch member being pivoted at 35. The differential or regulating field coil for the generator is shown at 36 and has one terminal connected to the positive side of the battery at 37, while its other terminal is adapted to'be connected between the field 30 and theresistance 32 at the point 38 by means of a switch 39 operated by, and simultaneously with, the main switch member. At 40 I show a lamp or work circuit connected across the battery 28. il represents a switch in series with the resistance 32, which is normally closed when the system is operated.

The operation of the system is mainly the same as the operation of the system shown in Fig. 1. Upon the voltage of the generator 25 rising to a suflicient value the main switch 32' closes, thereby connecting the battery and work circuit in series with the generator. At the same time coil 36 is connected across the points 37 and 38 by means of the switch 39. It is important, however, to have the coil 36 open circuited when starting up the system as otherwise a current would flow therein which would buck the coil 36 and prevent the system starting up so quickly. With this coil open circuited, howevergthe coil 30 is, on starting up, supplied from the battery 28 from the positive side of the battery through the resistance 29 to the coil 30, thence through the resistance 32 and back through the switch 41 to the negative side of the battery. When the system is shut down the switch 41 is opened in order to disconnect the battery from this coil. After the generator voltage has risen sufficiently to cause the main switch to close, the coil 36 acts either as a bucking or boosting coil according as the current in resistance 29 is low or tends to be high. It will be seen that as the generator current rises the voltage across the resistance 29 also rises, so that the current in the coil 36 not only varies with the current flowing to the battery but the current so in said coil flows in one direction when the current exceeds a predetermined value and in another direction when the current drops below a predetermined value.

If desired a field coil 43 may be connected across the resistance 32, asshown in Fig. 2, in which case still more of the energy absorbed in the left hand side of the \lheatstone bridge would be utilized in producing a field for the generator In either case, however, the coil 36 or the coil 20 is connected across the lVheatstone bridge for the purpose of regulating the generator whereby the current in the coil varies with the voltage across the battery for maintaining the voltage of the system substantially constant.

In Fig. 3 I show a modified arrangement in which the Wheatstone bridge is connected across the'generator in a slightly different manner. Referring to said Fig. 3, 51 and 53 represent the d. c. and a. 0. ends respectively of a double current generator having a main shunt field 52 and a differential field 55. The generator supplies the mains 58 and 59. 56 is a resistance in series with the battery 57 and work circuit 64, the latter two being in parallel with one another. A switch 65 is provided in the lamp circuit. 62 represents a main switch of any suitable. 110 kind. 54 represents a balancing coil to the neutral point of which is connected one terminal of the differential field so that it will be seen that the coil 54 plus the resistance of the armature forms two legs of a Wheatstone bridge, the other two legs being the resistance 56 and battery 57. the coil 55 being connected across said Wheatstone bridge so that when the current falls below a predetermined point' a current is caused to flow from the neutral through the differential coil 55 in the direction of the arrow 60, so as to increase the strength of the main field of the generator. If, however, the potential of the battery rises above this predetermined value the current is caused to flow in the reverse direction through the field 55, in the direction of the arrow 61, thereby producing a bucking effect on the main generator field. This scheme is applicable to any 130 three wire generator. 63 represents a switch in series with the main field 52.

In Fig. 4, represents the a. c.d. c. generat0r,'7l the balancing coil. 72 the battery, 78 the main field coil and 74 the series or regulating coil. The generator current passes through resistance coil H to coil 73 and battery 72. \Vith increasing current in coil 74 and corresponding increasing I It drop thereacross, the potential across coil 73 will be decreased thereby decreasing the field strength of the generator and limiting the increase of generator current due to speed increases. The coil 7 l is wound differentially to coil 73, thereby assisting in decreasing the field strength as the generator output rises.

Fig. 5 illustrates an arrangement similar to Fig. 4, except that the series field coil 74 is replaced by a simple resistance 7 t and all the regulation is produced or performed by the coil 73.

In Fig. 6 the arrangement and operation is like that of Fig. 5. except that the main field excitation is obtained by a coil 75 connected across the battery. while the coil 73 performs the duty of regulating by producing an opposing flux which increases with the generator output.

In Fig. 7. 76 represents the generator. 82 the battery, 77 the balancing coil and 78 the field coil. The field coil'78 is divided-into two parts 79 and 80 with the resistance 81 connected between the junction of coils 7t) and 80 and the positive main of the generator. In this arrangement the current in coil 7 9 decreases as the output rises. while that in coil 80 passes in the same direction as that through coil 79 until a predetermined value of generator current is reached, whereupon it reverses and causes coil 80 to oppose coil 79 and prevent the enerator current from going n'iaterially hig er.

Fig. 8 shows a similar arrangement, ex cept that the coil 79 is replaced by a simple resistance 79'. while the simple resistance 81 is replaced by a main field coil 81 connected between the junction between coil 80 and resistance 81' and the negative main of the generator. "he coil 80 acts as the regulat ing coil which assists the main coil 81' until a predetern'iined value of generator current is reached. whereupon the current in coil 80 is reversed and opposes coil 31 to limit the generator current.

Although I have dcscribed my improvements in great detail and with respect to certain embodiments thereof, nevertheless I do not desire to be limited to such details except as clearly specified in the appended claims, since many changes and modifications may well be made by those skilled in the art without departing from the spirit and scope of my invention in its broader aspects.

Having fully and clearly described my imto secure by Letters Patent. is: p

1. An electrical system of distribution having in combination, a generator driven at variable speed. provided with a' shunt field and a regulating field, a \Yhe'atstone bridge connected across said generator provided with a storage battery as one leg thereof. and a work circuit connected across the storage battery leg. said regulating field being connected across said \Vheatstone bridge. whereby the current therein varies with the generator current.

:2. An electrical system of distribution having in combination. a generator driven at variable speed. a 'hcatstoue bridge connected across said generator provided with a storage battery as one element thereof. a work circuit connected across the storage battery. and a coil for regulating the field of the generator, said coil being connected across said \Yheatstone bridge. whereby the current therein reverses according as the generator current exceeds or drops below certain values.

3. An electrical system of distribution having in combination a generator driven at variable speed. a storage batter and work circuit connected in parallel with one an other and in series with the generator. two resistances connected across the generator in series with one another and in parallel with the battery. and a third resistance connected in series with the generator between the batteryand the generator. said generator being provided with a shunt field and a field having one terminal connected between said first two resistances and its other terminal connected between the battery and said third resistance.

4. An electrical system of distribution having in combination a storage battery. a generator feeding said battery. and means for regulating the voltage of the generator to limit the generator current. said means embracing a plurality of resistances arranged in the form of a \Vheatstone bridge. and a coil connected thereto serially con.- nected between the generator and battery such that when the current therein exceeds a predetermined value the current in the coil is in one direction and when the generator current is below a predetermined value the current in the coil is in the othcr direction.

5. An electrical system of distribution having in combination a storage battery. a generator feeding said battery. a \Vhcatstone bridge arrangement. the battery forming one element thereof. and a coil conprovements, what I claim as new and desire net-ted across said bridge arrangement for 1 thereto, and means for regulating the voltage of the generator embracing a Wheatstone bridge arrangement operatively connected to be responsive to variations of current going to the storage battery and means whereby the field of the generator is controlled from said \Vheatstone bridge arrangement.

means wherebv the field of the gene 'ator is controlled from said \Vheatstone bridge arrangement to regulate the voltage of and the current delivered by the generator. I

8. An electrical system of distribution having in combination a sto age battery and work circuit, a generator feeding said battery and work circuit in parallel, said generator being provided with a main shunt field and a field for regulating the field strength of said generator responsive to changes in battery current, the current in said coil fiowing in one direction when the battery current exceeds a predetermined value, and in the other direction when the battery current is below a predetermined value, and a main switch for disconnecting the battery and work circuit from the generatorand rendering said regulating field inoperative when the generator voltage drops below a predetermined value.

9. A system of regulation emb acing a generator having a main field and a regulating field in combination with. a \Vheatstone bridge connected across the generator, said regulating coil being connected across said Wheatstone bridge and a storage battery forming one leg of the bridge.

10. The combination of a source of eleetrical energy to be regulated, a Vheatstone bridge connected across said source and naving a storage battery forming one leg thereof, and a coil regulating the voltage of said source connected across saidbridge.

11. An electrical system of distribution comprising a variable speed'generator and a storage battery fed thereby, a resistance in series with the storage battery, and a coil for regulating the voltage of the generator, the current in said coil being responsive to variations in the I R drop across said resistance and reversing when said I R drop reaches and exceeds a predetermined value.

' said resistance.

13. An electrical system of distribution comprising a variable speed generator and a storage battery fed thereby, a Wheatstone bridge having as one of its elements the storage battery and as another element a resistance in series with the storage battery,

- and a coil for regulating the voltage of the generator, the current in said coil being responsive to variations in the I R drop across said resistance, and reversing when said I R drop reaches and exceeds a predetermined value.

14. An electrical system of distribution comprising a generator, a storage battery and translating devices in operative relation thereto, and means for regulating the voltage of the generator embracing a IVheatstone bridge arrangement operatively connected to be responsive to variations of current going to the storage battery and to voltage variations across the battery and a coil regulating the field of the generator controlled from said IVheatstone bridge arrangement to regulate the voltage of and the current delivered by the generator.

15. An electrical system of distribution comprising a generator, a storage battery and translating'devices in operative relation thereto, and means for regulating the voltage of the generator embracing a Wheatstone bridge arrangement operatively connected to be responsive to variations of current going to the storage battery and means whereby the field of the generator is controlled from said IVheatstone bridge arrangement and a main switch .for automatically disconnecting the battery and translating devices from the generator and connections whereby said switch renders the regulating means ineifective when the generator is sodisconnected.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

I GEORGE RFESSENDEN, JR.

"Witnesses EDWARD HEWSON, P. W. ENGLISH.v

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

